Formins: the key regulators of plant cell morphology and development / 生物工程学报

Formins are widely distributed in eukaryotes such as fungi, plants and animals. They play crucial roles in regulating the polymerization of actin, coordinating the synergistic interactions between actin and microtubules, and determining cell growth and morphology. Unlike formins from fungi and animals, plant formins have been evolved into two plant-specific types. Generally, type Ⅱ formins are believed to regulate the polarized growth of cells, and type Ⅰ formins may regulate the cell expansion and division processes. Recent studies on the function of plant formins suggest it is inappropriate to classify the function of formins purely based on their structures. This review summarizes the domain organization of formins and their corresponding functions, as well as the underpinning mechanisms. Furthermore, the unsolved or unexplored issues along with future perspectives on plant formins are proposed and discussed.

The dynamic structure of Spitzenkörpers of Trichosporon asahii examined by the fluorescent probe FM4-64

Abstract The Spitzenkörper is a dynamic and specialized multicomponent cell complex present in the tips of hyphal cells. The amphiphilic styryl dye FM4-64 was found to be ideal for imaging the dynamic changes of the apical vesicle cluster within growing hyphal tips. It is widely used as a marker of endocytosis and to visualize vacuolar membranes. Here we performed uptake experiments using FM4-64 to study the dynamic of the Spitzenkörper in Trichosporon asahii. We observed that Spitzenkörpers were present at the tip of the budding site of the spore, blastospore, and the germ tube of T. asahii. We also found that Spitzenkörpers were present at the tip of the hyphae as well as the subapical regions. Cytochalasin D, an inhibitor of actin polymerization, leads to abnormal Spitzenkörper formation and loss of cell polarity.